The Left has traditionally assumed that human nature is so malleable, so perfectible, that it can be shaped in almost any direction. By contrast, a Darwinian science of human nature supports traditionalist conservatives and classical liberals in their realist view of human imperfectibility, and in their commitment to ordered liberty as rooted in natural desires, cultural traditions, and prudential judgments. Arnhart's email address is larnhart1@niu.edu.

Wednesday, December 09, 2009

The Evolutionary Biology of Empathy

The English word empathy was coined at the beginning of the 20th century as a translation of the German word Einfuhlung, which literally means "feeling into." Although many psychologists have distinguished empathy and sympathy, they seem in fact to be basically similar (Jahoda 2005).

Beginning in the 18th century, sympathy became an important philosophical concept for the moral psychology of Hume and Smith. For Smith, sympathy was understood broadly as "fellow feeling"--the capacity for sharing the emotions and thoughts of others--and it was the primary bond for social life and morality. Darwin adopted this Humean and Smithian moral psychology of sympathy, and he tried to explain its adaptive function in the evolutionary history of human beings as a primary ground for the "moral sense."

As studied by psychologists and biologists, empathy is a complex combination of many features (Decety and Jackson 2004; Decety and Ickes 2009). Empathy at its fullest includes feeling what another person is feeling, consciously understanding what another person is feeling, and responding to the needs of others.

The deepest and most primitive level of empathy is emotional contagion, the tendency to automatically resonate with other human beings by mimicking their facial expressions, vocal sounds, and bodily movements. This does not require any conscious awareness. Empathy begins with the synchronization of bodies, which has a bonding effect. Darwin saw this as a crucial manifestation of the natural sociality of humans and other animals in the expression of emotions (in his book The Expression of Emotions in Man and Animals).

Social activities like music, dancing, and marching in formation synchronize bodies in ways that create a convergence of emotions. That's why so many social ceremonies employ these kinds of activities to create social bonds.

The innate propensity to empathy is manifest in the natural inclination of human infants to imitation. Newborns cry in response to the distress cries of other newborns, but not to the recorded sound of their own cries. They resonate with the emotions of other human beings, while showing a self-awareness in distinguishing self and other.

The neural capacity for empathy surely arises from genetic traits that evolved in mammals to facilitate parental care of offspring, because parents need to understand and respond to the emotional needs of their offspring (Preston and de Waal 2002; de Waal 2009). In the evolution of ever more complex social life, this mammalian capacity for empathy was adapted for social feeling and social cognition that would allow individuals to synchronize their feelings and thoughts in cooperative activity. In primates, mirror neuron systems allow individuals to mentally simulate the subjective experience of others.

Through group selection, empathy evolved to promote in-group cooperation (de Waal 2009). Consequently, empathy is evoked by the proximity and familiarity that promotes identification. But while group identification enhances empathy within a group, it can also create hostility towards those outside the group. This can be seen in chimpanzees in the wild who sometimes engage in brutally violent warfare between territorial groups. In such warfare, as Jane Goodall observed, it seems that the victims have been "dechimpized," because they suffer from predatory violence usually displayed only against prey animals. This suggests the same kind of xenophobic suppression of identification that marks dehumanization in human warfare. More generally, human beings are more cooperative with those they recognize as in-group members than with those outside the group (de Waal 2009; Berreby 2005; Sturmer et al. 2005).

As a personality trait, empathy varies across individuals. On average, women seem to show more empathic propensities than men, a difference manifest even in infants.

The absence of empathy is evident in the psychopathic personality (Blair et al. 2005). Psychopathy is extremely rare. Although psychopathic tendencies might be as high as 1-3% of the human population, pure psychopathy is probably less than 1%, and in this small group, there are probably three times as many men as women. Psychopathy is a form of emotional disorder, which impedes the emotional learning of morality. Psychopaths are emotionally impaired in ways that make them less empathic to the suffering of others and less inclined to feel or understand moral emotions. The impaired emotional responsiveness and emotional learning in psychopaths seems to arise from the reduced responsiveness of neurons in the amygdala due to some genetic abnormality.